1==============
2OpenRISC Linux
3==============
4
5This is a port of Linux to the OpenRISC class of microprocessors; the initial
6target architecture, specifically, is the 32-bit OpenRISC 1000 family (or1k).
7
8For information about OpenRISC processors and ongoing development:
9
10	=======		=============================
11	website		https://openrisc.io
12	email		openrisc@lists.librecores.org
13	=======		=============================
14
15---------------------------------------------------------------------
16
17Build instructions for OpenRISC toolchain and Linux
18===================================================
19
20In order to build and run Linux for OpenRISC, you'll need at least a basic
21toolchain and, perhaps, the architectural simulator.  Steps to get these bits
22in place are outlined here.
23
241) Toolchain
25
26Toolchain binaries can be obtained from openrisc.io or our github releases page.
27Instructions for building the different toolchains can be found on openrisc.io
28or Stafford's toolchain build and release scripts.
29
30	==========	=================================================
31	binaries	https://github.com/openrisc/or1k-gcc/releases
32	toolchains	https://openrisc.io/software
33	building	https://github.com/stffrdhrn/or1k-toolchain-build
34	==========	=================================================
35
362) Building
37
38Build the Linux kernel as usual::
39
40	make ARCH=openrisc CROSS_COMPILE="or1k-linux-" defconfig
41	make ARCH=openrisc CROSS_COMPILE="or1k-linux-"
42
433) Running on FPGA (optional)
44
45The OpenRISC community typically uses FuseSoC to manage building and programming
46an SoC into an FPGA.  The below is an example of programming a De0 Nano
47development board with the OpenRISC SoC.  During the build FPGA RTL is code
48downloaded from the FuseSoC IP cores repository and built using the FPGA vendor
49tools.  Binaries are loaded onto the board with openocd.
50
51::
52
53	git clone https://github.com/olofk/fusesoc
54	cd fusesoc
55	sudo pip install -e .
56
57	fusesoc init
58	fusesoc build de0_nano
59	fusesoc pgm de0_nano
60
61	openocd -f interface/altera-usb-blaster.cfg \
62		-f board/or1k_generic.cfg
63
64	telnet localhost 4444
65	> init
66	> halt; load_image vmlinux ; reset
67
684) Running on a Simulator (optional)
69
70QEMU is a processor emulator which we recommend for simulating the OpenRISC
71platform.  Please follow the OpenRISC instructions on the QEMU website to get
72Linux running on QEMU.  You can build QEMU yourself, but your Linux distribution
73likely provides binary packages to support OpenRISC.
74
75	=============	======================================================
76	qemu openrisc	https://wiki.qemu.org/Documentation/Platforms/OpenRISC
77	=============	======================================================
78
79---------------------------------------------------------------------
80
81Terminology
82===========
83
84In the code, the following particles are used on symbols to limit the scope
85to more or less specific processor implementations:
86
87========= =======================================
88openrisc: the OpenRISC class of processors
89or1k:     the OpenRISC 1000 family of processors
90or1200:   the OpenRISC 1200 processor
91========= =======================================
92
93---------------------------------------------------------------------
94
95History
96========
97
9818-11-2003	Matjaz Breskvar (phoenix@bsemi.com)
99	initial port of linux to OpenRISC/or32 architecture.
100        all the core stuff is implemented and seams usable.
101
10208-12-2003	Matjaz Breskvar (phoenix@bsemi.com)
103	complete change of TLB miss handling.
104	rewrite of exceptions handling.
105	fully functional sash-3.6 in default initrd.
106	a much improved version with changes all around.
107
10810-04-2004	Matjaz Breskvar (phoenix@bsemi.com)
109	a lot of bugfixes all over.
110	ethernet support, functional http and telnet servers.
111	running many standard linux apps.
112
11326-06-2004	Matjaz Breskvar (phoenix@bsemi.com)
114	port to 2.6.x
115
11630-11-2004	Matjaz Breskvar (phoenix@bsemi.com)
117	lots of bugfixes and enhancements.
118	added opencores framebuffer driver.
119
12009-10-2010    Jonas Bonn (jonas@southpole.se)
121	major rewrite to bring up to par with upstream Linux 2.6.36
122